First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.
Continue in the practice tool above to load more questions, 50 at a time.
Question 1Speech
A speech-language pathologist is assessing a child whose speech shows a consistent substitution of /t/ for /k/ and /d/ for /g/, with all other consonants produced accurately. This pattern is best described as which type of error?
- Stopping of fricatives
- Final consonant deletion
- Velar fronting Correct answer.
- Cluster reduction
Explanation
Velar fronting is the replacement of back velar sounds /k/ and /g/ with front alveolar sounds /t/ and /d/, often described as fronting the place of articulation. The other listed patterns involve consonant clusters, word-final consonants, or fricatives, none of which matches the described substitution.
Question 2Speech
During an oral mechanism examination, a client is asked to say "ah" while the examiner observes the soft palate. Which observation would most directly indicate velopharyngeal incompetence during speech?
- The velum fails to elevate sufficiently, leaving a gap during sustained phonation Correct answer.
- The tongue retracts strongly toward the posterior pharyngeal wall
- The velum elevates and contacts the posterior pharyngeal wall during phonation
- The lips round excessively during vowel production
Explanation
Velopharyngeal closure requires the soft palate to elevate and meet the posterior pharyngeal wall so that air does not escape through the nose during oral speech sounds. Incompetence is marked by incomplete elevation or incomplete contact, producing hypernasality and nasal emission.
Question 3Speech
A kindergarten teacher reports that a student omits the plural -s marker in conversational speech but produces it correctly when imitating the teacher. Which conclusion is most appropriate for the speech-language pathologist?
- The student has a structural deficit requiring medical referral
- The student is using a dialectal variation that requires no intervention
- The student has not yet internalized the morphological rule in spontaneous speech Correct answer.
- The student's hearing should be ruled out as the sole cause of the omission
Explanation
When a child produces a form correctly in imitation but omits it spontaneously, the underlying production capacity is present and the difficulty lies in consistent application of the morphological rule. This pattern points to a language-learning or generalization issue rather than a structural or sensory limitation.
Question 4Speech
A client with a fluency disorder reports that stuttering worsens when speaking on the telephone and improves when reading aloud alone. Which factor is most clearly influencing fluency in this case?
- Syntactic complexity of the message
- Reduced respiratory capacity
- Communicative pressure and listener presence Correct answer.
- Motor speech programming deficits
Explanation
Fluency that deteriorates in demanding communicative situations and improves when the speaker is alone reflects the influence of communicative pressure and the presence of a listener. These situational factors are commonly documented in fluency assessment and are distinct from linguistic complexity or motor programming.
Question 5Speech
A 7-year-old produces /s/ with the tongue tip protruding between the teeth. Which term describes this error?
- Frontal lisp Correct answer.
- Dentalization of /r/
- Nasal emission
- Lateral lisp
Explanation
A frontal lisp occurs when the tongue tip protrudes between the front teeth during /s/ or /z/ production, producing a th-like sound. Lateral lisps direct air over the side of the tongue, and nasal emission involves airflow through the nose.
Question 6Speech
An examiner wants to determine whether a child can produce a target phoneme in increasingly complex contexts. Which assessment approach is most appropriate?
- A stimulability probe moving from isolation to syllables to words Correct answer.
- A language sample analyzed for mean length of utterance
- A hearing screening at multiple frequencies
- A standardized receptive vocabulary test
Explanation
Stimulability testing examines whether a client can produce a target sound when given a model, progressing from isolated sounds to syllables, words, and phrases. This information helps predict prognosis and guide treatment targets.
Question 7Speech
A client with apraxia of speech is practicing multisyllabic words. Which treatment principle is most consistent with evidence-based practice for this disorder?
- Reliance on conversational recasts alone
- Principle of motor learning with frequent, high-intensity practice and feedback Correct answer.
- Massed drill of nonsense syllables without feedback
- Exclusive use of written worksheets
Explanation
Apraxia treatment is grounded in motor learning principles, emphasizing intensive practice, distributed and variable practice conditions, and appropriate feedback to support motor planning and programming. Nonsense drill without feedback, written worksheets, and recasts alone do not address the core motor planning deficit.
Question 8Speech
A child says "tup" for "cup" and "dat" for "cat." Which phonological process is demonstrated?
- Gliding
- Velar fronting Correct answer.
- Stopping
- Assimilation
Explanation
Velar fronting replaces velar consonants /k/ and /g/ with alveolar sounds, so "cup" becomes "tup" and "cat" becomes "dat." The substitutions consistently move the place of articulation forward.
Question 9Speech
Which statement best describes the role of the arcuate fasciculus in speech and language processing?
- It regulates the velopharyngeal port during swallowing
- It controls the muscles of the larynx directly
- It is the primary center for auditory perception of pitch
- It connects Broca's and Wernicke's areas and supports repetition of language Correct answer.
Explanation
The arcuate fasciculus is a white matter tract linking Broca's area in the frontal lobe with Wernicke's area in the temporal lobe. Damage to this pathway is classically associated with conduction aphasia, in which repetition is disproportionately impaired.
Question 10Speech
A client with a right-hemisphere stroke shows difficulty understanding sarcasm, maintaining topic, and taking turns in conversation. Which area of communication is most impaired?
- Pragmatics and discourse Correct answer.
- Morphological rule use
- Phonological awareness
- Speech sound production
Explanation
Right-hemisphere damage commonly affects pragmatics, including interpreting nonliteral language, managing topic maintenance, and turn-taking. These discourse-level abilities are distinct from phonology, morphology, and articulation.
Question 11Speech
Which of the following is a characteristic feature of Wernicke's aphasia?
- Nonfluent speech with relatively preserved comprehension
- Severely impaired articulation with intact writing
- Preserved repetition with impaired comprehension of single words
- Fluent speech with poor comprehension and impaired repetition Correct answer.
Explanation
Wernicke's aphasia is a fluent aphasia marked by poor auditory comprehension and impaired repetition, often with paraphasic errors and anosognosia. Nonfluent output is characteristic of Broca's aphasia rather than Wernicke's.
Question 12Speech
A school-based speech-language pathologist wants to support a student's ability to define words and categorize them by meaning. Which language area is being targeted?
- Syntax
- Phonology
- Prosody
- Semantics Correct answer.
Explanation
Semantics concerns word meaning, including defining words, understanding relationships among words, and categorizing concepts. Syntax concerns sentence structure, phonology concerns sound patterns, and prosody concerns rhythm and intonation.
Question 13Speech
A client is described as having a flaccid dysarthria. Which speech characteristic is most consistent with this diagnosis?
- Irregular articulatory breakdowns with scanning speech
- Monotone pitch with rapid rate
- Hypernasality and weak, breathy phonation Correct answer.
- Harsh voice with strained-strangled quality
Explanation
Flaccid dysarthria results from lower motor neuron damage and produces weakness, including hypernasality from velopharyngeal weakness and breathy phonation from laryngeal weakness. Strained-strangled voice suggests spastic dysarthria, and irregular breakdowns suggest ataxic dysarthria.
Question 14Speech
Which measure is most appropriate for documenting a client's ability to produce a target sound accurately in spontaneous conversation after treatment?
- Audiometric thresholds at 500 Hz
- Number of words read per minute
- Standard score on a receptive language test
- Percentage of correct productions in a conversational speech sample Correct answer.
Explanation
Generalization of a treated sound to spontaneous conversation is documented by calculating the percentage of correct productions in a conversational sample. Standard scores, reading rate, and audiometric thresholds do not measure carryover of articulation targets.
Question 15Speech
A child with a repaired cleft palate shows nasal emission and weak pressure consonants. Which intervention approach is most directly indicated?
- Encouraging rapid speech to mask the emission
- Increasing loudness without attention to airflow
- Velopharyngeal function activities and blowing/airflow tasks to build oral pressure Correct answer.
- Practicing only vowel sounds
Explanation
Nasal emission and weak pressure consonants reflect inadequate velopharyngeal closure and reduced intraoral pressure. Treatment targets improved oral airflow and velopharyngeal function, often paired with pressure consonant practice, and may require medical referral if closure is structurally inadequate.
Question 16Speech
Which of the following best defines a phoneme?
- A unit of pitch variation in speech
- A grammatical category of words
- The smallest unit of meaning in a language
- The smallest contrastive unit of sound in a language Correct answer.
Explanation
A phoneme is the smallest unit of sound that can distinguish meaning in a language, such as the difference between /p/ and /b/ in "pat" and "bat." The smallest unit of meaning is a morpheme.
Question 17Speech
A preschooler says "wabbit" for "rabbit" and "wamp" for "lamp." Which process is present?
- Cluster reduction
- Metathesis
- Epenthesis
- Gliding Correct answer.
Explanation
Gliding is the substitution of the liquid consonants /r/ and /l/ with the glides /w/ or /j/, producing forms such as "wabbit" and "wamp." Cluster reduction, epenthesis, and metathesis describe different structural changes to the word.
Question 18Speech
A speech-language pathologist is evaluating a client who reports food sticking in the throat, coughing during meals, and a wet vocal quality after eating. Which area should be the primary focus of assessment?
- Voice resonance
- Articulation of sibilants
- Auditory processing
- Swallowing function and airway protection Correct answer.
Explanation
Coughing during meals, a wet vocal quality after eating, and food sticking in the throat suggest dysphagia with possible aspiration risk. The primary assessment focus should be swallowing safety and airway protection, often including instrumental evaluation.
Question 19Speech
Which statement accurately describes the difference between speech and language?
- Speech is a cognitive process, while language is a motor process
- Speech refers to the sound production system, while language refers to the rule-based symbol system for communication Correct answer.
- Language refers only to written communication, while speech refers to spoken words
- Speech and language are interchangeable terms in communication sciences
Explanation
Speech is the motor act of producing sounds through the respiratory, phonatory, and articulatory systems. Language is a shared, rule-governed symbol system that includes phonology, morphology, syntax, semantics, and pragmatics and can be expressed in spoken, written, or signed forms.
Question 20Speech
A client produces the sentence "The boy eated three cookie" in a language sample. Which analysis best captures the errors?
- Two phonological errors
- One pragmatic error and one morphological error
- One morphological overgeneralization and one plural omission Correct answer.
- One syntactic error and one semantic error
Explanation
"Eated" is an overgeneralization of the regular past tense -ed to an irregular verb, which is a morphological error. "Cookie" lacks the plural -s despite the quantifier "three," which is also a morphological omission of plurality.
Question 21Speech
During an assessment, a bilingual child who speaks Spanish at home and English at school is being evaluated for a language disorder. Which practice is most appropriate?
- Assessing both languages and considering the child's language exposure history Correct answer.
- Assuming any difference from English monolingual norms indicates a disorder
- Testing only in English and comparing to English monolingual norms
- Deferring assessment until the child speaks only English
Explanation
Best practice for bilingual assessment requires evaluating both languages and gathering a thorough history of language exposure, because a true disorder will be evident across languages while a difference may reflect normal second-language acquisition. Testing only in English against monolingual norms risks misidentification.
Question 22Speech
A client with Parkinson's disease presents with reduced loudness, monopitch, and imprecise articulation. Which treatment approach is most strongly supported for this profile?
- Melodic intonation therapy
- Cognitive stimulation therapy
- Lee Silverman Voice Treatment (LSVT LOUD) Correct answer.
- Semantic feature analysis
Explanation
LSVT LOUD is an intensive voice treatment designed for hypokinetic dysarthria in Parkinson's disease, targeting increased vocal effort and loudness to improve overall speech production. The other approaches target aphasia or cognition rather than hypokinetic dysarthria.
Question 23Speech
A speech-language pathologist is analyzing a language sample and calculates the mean length of utterance in morphemes. Which aspect of language development does this measure primarily index?
- Voice quality
- Articulation accuracy
- Pragmatic appropriateness
- Grammatical complexity Correct answer.
Explanation
Mean length of utterance in morphemes is a widely used index of grammatical development, reflecting the increasing complexity of a child's syntax and morphology. It does not measure articulation, voice, or social use of language.
Question 24Speech
A client with suspected aspiration is scheduled for a videofluoroscopic swallow study. Which statement best describes the purpose of this procedure?
- It assesses receptive vocabulary
- It provides dynamic imaging of swallowing to identify aspiration and guide diet recommendations Correct answer.
- It measures pure-tone hearing thresholds
- It evaluates vocal fold vibration during phonation
Explanation
A videofluoroscopic swallow study uses fluoroscopy to visualize the oral, pharyngeal, and esophageal phases of swallowing in real time. It identifies aspiration, penetration, and residue and informs safe diet and treatment recommendations.
Question 25Speech
A child consistently uses a single word, "ball," to refer to all round objects, including oranges, balloons, and balls. Which term best describes this pattern?
- Overextension Correct answer.
- Underextension
- Fast mapping
- Telegraphic speech
Explanation
Overextension occurs when a child applies a word more broadly than its conventional meaning, using "ball" for any round object. Underextension is the opposite pattern, in which a word is used too narrowly.
Question 26Speech
A speech-language pathologist is describing the role of Broca's area in speech production. Which statement best characterizes its primary function?
- It decodes the acoustic signal during auditory comprehension.
- It programs the motor sequences needed to articulate spoken words. Correct answer.
- It coordinates the swallowing reflex during the pharyngeal phase.
- It stores the phonological representations of familiar words for later retrieval.
Explanation
Broca's area, located in the posterior inferior frontal gyrus of the dominant hemisphere, is associated with motor speech programming and expressive language output. Damage here typically produces nonfluent speech with effortful articulation, as seen in Broca's aphasia.
Question 27Speech
During a language sample, a child produces the utterance "Doggy runned fast" and "Two mouses." Which analysis most precisely describes these errors?
- Difficulty with consonant cluster reduction in multisyllabic words.
- Delayed onset of canonical babbling.
- Overgeneralization of regular past tense and plural morphemes to irregular forms. Correct answer.
- Persistent use of reduplication across all word classes.
Explanation
These errors reflect morphological overgeneralization, in which a child applies a regular grammatical rule (past tense -ed, plural -s) to irregular forms that do not follow it. This pattern is a normal developmental stage that usually resolves as the child acquires irregular forms.
Question 28Speech
A client with a left-hemisphere lesion produces fluent, grammatically well-formed but largely meaningless speech and shows poor comprehension. Which term best describes this pattern?
- Anomic aphasia
- Conduction aphasia
- Wernicke's aphasia Correct answer.
- Broca's aphasia
Explanation
Wernicke's aphasia is characterized by fluent but empty speech, impaired comprehension, and poor self-monitoring, reflecting damage to the posterior superior temporal region. The preserved fluency with impaired meaning distinguishes it from nonfluent syndromes.
Question 29Speech
A school-based SLP is selecting a standardized instrument to measure a child's receptive vocabulary. Which property of the test most directly indicates the consistency of scores across repeated administrations?
- Standardization sample
- Reliability Correct answer.
- Content validity
- Construct validity
Explanation
Reliability refers to the consistency and stability of test scores across repeated administrations or raters. Validity, by contrast, concerns whether the test measures the construct it claims to measure.
Question 30Speech
A child with a phonological disorder substitutes /t/ for /k/ and /d/ for /g/ consistently. Which process is demonstrated?
- Gliding
- Fronting Correct answer.
- Final consonant deletion
- Stopping
Explanation
Fronting occurs when velar sounds (/k/, /g/) are replaced by sounds produced further forward in the mouth (/t/, /d/). This pattern is a common developmental phonological process that typically resolves by around age four.
Question 31Speech
A client with a voice disorder is being evaluated for hoarseness and vocal fatigue. Which structure is primarily responsible for vocal fold vibration during phonation?
- The vocal folds (true vocal cords) within the larynx Correct answer.
- The aryepiglottic folds during swallowing
- The epiglottis during airway protection
- The soft palate during velopharyngeal closure
Explanation
The true vocal folds vibrate as air passes between them, producing the voice source during phonation. Their mass, tension, and approximation determine pitch and loudness.
Question 32Speech
An SLP is explaining the difference between speech and language to a parent. Which statement most accurately reflects the distinction?
- Speech and language are interchangeable terms for oral communication.
- Speech is the motoric production of sounds, while language is a rule-governed system for communication. Correct answer.
- Speech refers only to written symbols, while language refers only to spoken words.
- Language is the motor act of articulation, while speech is the underlying meaning system.
Explanation
Speech refers to the neuromuscular act of producing sounds, including articulation, voice, and fluency. Language is the broader symbolic system governing phonology, morphology, syntax, semantics, and pragmatics.
Question 33Speech
A client reports a sudden onset of slurred speech, facial droop, and arm weakness. Which action should the SLP take first?
- Recommend emergency medical evaluation for possible stroke. Correct answer.
- Schedule a routine voice evaluation for the following week.
- Treat the slurred speech as a primary articulation disorder.
- Begin fluency shaping techniques for stuttering.
Explanation
Sudden slurred speech with facial droop and limb weakness are classic warning signs of stroke and require immediate emergency medical evaluation. The SLP's priority is to facilitate urgent medical care rather than initiate speech treatment.
Question 34Speech
A client with dysarthria is being assessed for speech intelligibility. Which task most directly evaluates the speaker's ability to convey a message to a listener?
- Counting from one to ten
- Reading a standardized passage while a listener transcribes it Correct answer.
- Sustaining a vowel for maximum phonation time
- Producing a maximum vowel prolongation
Explanation
Intelligibility refers to how much of a spoken message a listener can understand. Having a listener transcribe connected speech directly measures the proportion of the message conveyed.
Question 35Speech
A child who is 3;6 consistently omits the final consonant in words like "cat" and "dog." Which intervention target is most appropriate based on the principles of phonological intervention?
- Drilling isolated /k/ sounds without context
- Targeting final consonant production in functional words Correct answer.
- Practicing multisyllabic nonsense words
- Working on /r/ in all positions
Explanation
Phonological intervention should target the process in meaningful, functional contexts rather than isolated sounds. Targeting final consonants in real words directly addresses the deletion process and supports generalization.
Question 36Speech
An SLP is evaluating a client who has difficulty planning and sequencing the movements needed for speech, with inconsistent errors and groping. Which diagnosis is most consistent with this presentation?
- Aphasia
- Spasmodic dysphonia
- Flaccid dysarthria
- Apraxia of speech Correct answer.
Explanation
Apraxia of speech is a motor planning disorder characterized by inconsistent errors, groping, and difficulty sequencing articulatory movements. The inconsistency and effortful searching distinguish it from dysarthria.
Question 37Speech
A client with aphasia is being assessed for the ability to repeat words and sentences. Which perisylvian syndrome typically shows markedly impaired repetition with relatively preserved comprehension?
- Wernicke's aphasia
- Anomic aphasia
- Conduction aphasia Correct answer.
- Transcortical sensory aphasia
Explanation
Conduction aphasia is characterized by disproportionately impaired repetition with relatively preserved comprehension, often due to damage to the arcuate fasciculus. Transcortical sensory aphasia, by contrast, spares repetition.
Question 38Speech
An SLP is working with a child who uses only two-word combinations and has a limited vocabulary at age three. Which intervention approach most directly supports early syntactic development?
- Practicing articulation of late-developing sounds
- Drilling isolated vocabulary flashcards
- Modeling and expanding the child's utterances during play Correct answer.
- Using a communication board exclusively
Explanation
Expansion and modeling during naturalistic play support the transition to longer utterances by providing enriched input just beyond the child's current level. This technique is grounded in the zone of proximal development.
Question 39Speech
A client with a swallowing disorder is being evaluated for risk of aspiration. Which finding most strongly suggests aspiration during meals?
- Occasional throat clearing between meals
- Mild drooling while sleeping
- Coughing during or immediately after swallowing Correct answer.
- Complaints of dry mouth in the morning
Explanation
Coughing during or immediately after swallowing is a classic sign of aspiration, indicating that material has entered the airway. This triggers a protective cough reflex.
Question 40Speech
An SLP is analyzing a child's speech and notes that the child substitutes a glide for /r/ and /l/, producing "wabbit" and "yamp." Which process is present?
- Gliding Correct answer.
- Cluster reduction
- Fronting
- Stopping
Explanation
Gliding is the substitution of a glide (/w/ or /j/) for a liquid (/r/ or /l/). It is a common developmental process that typically resolves by around age six.
Question 41Speech
A client with Parkinson's disease presents with reduced loudness, monopitch, and imprecise articulation. Which treatment approach is most strongly supported by evidence for this population?
- Semantic feature analysis
- Voice banking for future augmentative communication
- Lee Silverman Voice Treatment (LSVT LOUD) Correct answer.
- Melodic intonation therapy
Explanation
LSVT LOUD is an intensive voice treatment with strong evidence for improving loudness and speech intelligibility in Parkinson's disease. It targets increased vocal effort and amplitude.
Question 42Speech
A bilingual child is being evaluated for a language disorder. Which practice most reduces the risk of misidentifying a typically developing bilingual child as language impaired?
- Administering only nonverbal IQ tests
- Testing only in English using monolingual norms
- Assessing the child in both languages and comparing to bilingual norms Correct answer.
- Relying solely on teacher report of classroom performance
Explanation
Best practice in bilingual assessment involves evaluating both languages and using appropriate bilingual normative data to distinguish language difference from disorder. Monolingual norms can overidentify typically developing bilingual children.
Question 43Speech
An SLP calculates mean length of utterance in morphemes (MLU) from a language sample. Which statement best describes the clinical utility of MLU?
- It provides a developmental index of syntactic complexity in young children. Correct answer.
- It measures articulation accuracy across all phonemes.
- It determines the presence of voice disorders.
- It quantifies receptive vocabulary size.
Explanation
MLU in morphemes is a widely used index of grammatical development and syntactic complexity in young children. It correlates with developmental language milestones and helps identify language delay.
Question 44Speech
A child consistently uses the word "ball" to refer to all round objects, including oranges and balloons. Which term best describes this pattern?
- Telegraphic speech
- Underextension
- Fast mapping
- Overextension Correct answer.
Explanation
Overextension occurs when a child applies a word too broadly to objects that share features with the original referent. It is a normal early lexical development pattern.
Question 45Speech
An SLP is asked to determine whether a treatment is producing meaningful change beyond measurement error. Which approach best supports this determination?
- Reviewing only anecdotal reports from family members
- Comparing pre- and post-treatment scores using a reliable change index Correct answer.
- Administering a single probe at discharge
- Relying on the clinician's subjective impression alone
Explanation
A reliable change index accounts for measurement error and establishes whether observed change exceeds what would be expected by chance or test unreliability. This strengthens conclusions about treatment effects.
Question 46Speech
A client with severe dysarthria and limited intelligibility is being considered for augmentative and alternative communication (AAC). Which principle best guides the SLP's decision?
- AAC should be introduced only after all natural speech has been lost.
- AAC should be considered when it enhances functional communication, even if some natural speech remains. Correct answer.
- AAC should replace all other communication modalities immediately.
- AAC should be withheld until the client requests it.
Explanation
AAC is appropriate whenever it supports or enhances functional communication, and it can coexist with residual natural speech. Early introduction often improves outcomes and participation.
Question 47Speech
An SLP is analyzing a client's connected speech and finds frequent phonemic paraphasias, self-corrections, and relatively preserved comprehension but impaired repetition. Which syndrome is most consistent with this profile?
- Conduction aphasia Correct answer.
- Broca's aphasia
- Global aphasia
- Transcortical motor aphasia
Explanation
Conduction aphasia is characterized by phonemic paraphasias, preserved comprehension, and disproportionately impaired repetition, often linked to arcuate fasciculus damage. Self-corrections reflect awareness of errors.
Question 48Speech
A researcher is examining whether a new phonological treatment generalizes to untreated sounds. Which outcome measure best captures generalization?
- Client satisfaction ratings
- Accuracy on untreated phonemes in untrained contexts Correct answer.
- Accuracy on trained phonemes during drill
- Attendance at treatment sessions
Explanation
Generalization refers to the extension of learned skills to untrained targets or contexts. Measuring accuracy on untreated phonemes in untrained contexts directly assesses this transfer.
Question 49Speech
An SLP is evaluating a child who speaks a nonmainstream dialect at home. Which approach best distinguishes dialect difference from disorder?
- Comparing the child only to standard English norms
- Assuming any nonstandard form reflects disorder
- Analyzing the child's errors against the rules of the child's dialect Correct answer.
- Testing only articulation of standard English phonemes
Explanation
Distinguishing difference from disorder requires analyzing the child's speech against the rules of their dialect rather than standard English alone. Features consistent with the dialect are not errors.
Question 50Speech
A client with a fluency disorder is being evaluated. Which measure best quantifies the frequency of stuttering-like disfluencies in a speech sample?
- Percentage of syllables stuttered Correct answer.
- Maximum phonation time
- Type-token ratio
- Speaking rate in syllables per minute
Explanation
Percentage of syllables stuttered quantifies the proportion of stuttered syllables relative to total syllables, providing a standardized index of stuttering frequency. It is widely used in fluency assessment.